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Article
Publication date: 14 January 2014

Yong Liu, Dingbing Shi and Steven Baard Skaar

Vision-based positioning without camera calibration, using uncalibrated industrial robots, is a challenging research problem. To address the issue, an uncalibrated…

Abstract

Purpose

Vision-based positioning without camera calibration, using uncalibrated industrial robots, is a challenging research problem. To address the issue, an uncalibrated industrial robot real-time positioning system has been developed in this paper. The paper aims to discuss these issues.

Design/methodology/approach

The software and hardware of this system as well as the methodology are described. Direct and inverse kinematics equations that map joint space into “camera space” are developed. The camera-space manipulation (CSM) algorithm has been employed and improved with varying weights on camera samples of the robot end effector, and the improved CSM is named VW-CSM. The experiments of robot positioning have been conducted using the traditional CSM algorithm and the varying-weight CSM (VW-CSM) algorithm, respectively, both without separate camera calibration. The impact on the accuracy and real-time performance of the system caused by different weights has been examined and discussed.

Findings

The experimental results show that the accuracy and real-time performance of the system with the VW-CSM algorithm is better than the one with using the original CSM algorithm, and the impact on the accuracy and real-time performance of the system caused by different weights has been revealed.

Originality/value

The accuracy and real-time performance of the system with the VW-CSM algorithm is verified. These results prove that the developed system using the VW-CSM algorithm can satisfy the requirements of most industrial applications and can be widely used in the field of industrial robots.

Details

Industrial Robot: An International Journal, vol. 41 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 20 April 2020

J. Guillermo Lopez-Lara, Mauro Eduardo Maya, Alejandro González, Antonio Cardenas and Liliana Felix

The purpose of this paper is to present a new vision-based control method, which enables delta-type parallel robots to track and manipulate objects moving in arbitrary…

Abstract

Purpose

The purpose of this paper is to present a new vision-based control method, which enables delta-type parallel robots to track and manipulate objects moving in arbitrary trajectories. This constitutes an enhanced variant of the linear camera model-camera space manipulation (LCM-CSM).

Design/methodology/approach

After obtaining the LCM-CSM view parameters, a moving target’s position and its velocity are estimated in camera space using Kalman filter. The robot is then commanded to reach the target. The proposed control strategy has been experimentally validated using a PARALLIX LKF-2040, an academic delta-type parallel platform and seven different target trajectories for which the positioning errors were recorded.

Findings

For objects that moved manually along a sawtooth, zigzag or increasing spiral trajectory with changing velocities, a maximum positioning error of 4.31 mm was found, whereas objects that moved on a conveyor belt at constant velocity ranging from 7 to 12 cm/s, average errors between 2.2-2.75 mm were obtained. For static objects, an average error of 1.48 mm was found. Without vision-based control, the experimental platform used has a static positioning accuracy of 3.17 mm.

Practical implications

The LCM-CSM method has a low computational cost and does not require calibration or computation of Jacobians. The new variant of LCM-CSM takes advantage of aforementioned characteristics and applies them to vision-based control of parallel robots interacting with moving objects.

Originality/value

A new variant of the LCM-CSM method, traditionally used only for static positioning of a robot’s end-effector, was applied to parallel robots enabling the manipulation of objects moving along unknown trajectories.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 15 May 2017

Zhenyu Li, Bin Wang, Haitao Yang and Hong Liu

Rapid satellite capture by a free-floating space robot is a challenge problem because of no-fixed base and time-delay issues. This paper aims to present a modified target…

Abstract

Purpose

Rapid satellite capture by a free-floating space robot is a challenge problem because of no-fixed base and time-delay issues. This paper aims to present a modified target capturing control scheme for improving the control performance.

Design/methodology/approach

For handling such control problem including time delay, the modified scheme is achieved by adding a delay calibration algorithm into the visual servoing loop. To identify end-effector motions in real time, a motion predictor is developed by partly linearizing the space robot kinematics equation. By this approach, only ground-fixed robot kinematics are involved in the predicting computation excluding the complex space robot kinematics calculations. With the newly developed predictor, a delay compensator is designed to take error control into account. For determining the compensation parameters, the asymptotic stability condition of the proposed compensation algorithm is also presented.

Findings

The proposed method is conducted by a credible three-dimensional ground experimental system, and the experimental results illustrate the effectiveness of the proposed method.

Practical implications

Because the delayed camera signals are compensated with only ground-fixed robot kinematics, this proposed satellite capturing scheme is particularly suitable for commercial on-orbit services with cheaper on-board computers.

Originality/value

This paper is original as an attempt trying to compensate the time delay by taking both space robot motion predictions and compensation error control into consideration and is valuable for rapid and accurate satellite capture tasks.

Details

Industrial Robot: An International Journal, vol. 44 no. 3
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 September 2005

Mario Peña‐Cabrera, Ismael Lopez‐Juarez, Reyes Rios‐Cabrera and Jorge Corona‐Castuera

Outcome with a novel methodology for online recognition and classification of pieces in robotic assembly tasks and its application into an intelligent manufacturing cell.

Abstract

Purpose

Outcome with a novel methodology for online recognition and classification of pieces in robotic assembly tasks and its application into an intelligent manufacturing cell.

Design/methodology/approach

The performance of industrial robots working in unstructured environments can be improved using visual perception and learning techniques. The object recognition is accomplished using an artificial neural network (ANN) architecture which receives a descriptive vector called CFD&POSE as the input. Experimental results were done within a manufacturing cell and assembly parts.

Findings

Find this vector represents an innovative methodology for classification and identification of pieces in robotic tasks, obtaining fast recognition and pose estimation information in real time. The vector compresses 3D object data from assembly parts and it is invariant to scale, rotation and orientation, and it also supports a wide range of illumination levels.

Research limitations/implications

Provides vision guidance in assembly tasks, current work addresses the use of ANN's for assembly and object recognition separately, future work is oriented to use the same neural controller for all different sensorial modes.

Practical implications

Intelligent manufacturing cells developed with multimodal sensor capabilities, might use this methodology for future industrial applications including robotics fixtureless assembly. The approach in combination with the fast learning capability of ART networks indicates the suitability for industrial robot applications as it is demonstrated through experimental results.

Originality/value

This paper introduces a novel method which uses collections of 2D images to obtain a very fast feature data – ”current frame descriptor vector” – of an object by using image projections and canonical forms geometry grouping for invariant object recognition.

Details

Assembly Automation, vol. 25 no. 3
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 20 March 2017

Payam Zarafshan, Reza Larimi, S. Ali A. Moosavian and Bruno Siciliano

The purpose of this paper is to present a comparison study of cooperative object manipulation control algorithms. To this end, a full comprehensive survey of the existing…

Abstract

Purpose

The purpose of this paper is to present a comparison study of cooperative object manipulation control algorithms. To this end, a full comprehensive survey of the existing control algorithms in this field is presented.

Design/methodology/approach

Cooperative manipulation occurs when manipulators are mechanically coupled to the object being manipulated, and the manipulators may not be treated as an isolated system. The most important and basic impedance control (IC) strategies for an assumed cooperative object manipulation task are the Augmented Object Model (AOM) control and the multiple impedance control (MIC) which are found based on the IC, where the former is designed based on the object movement, and the latter is designed based on the whole robot movement. Thus, the basis of these two algorithms are fully studied.

Findings

The results are fully analyzed, and it is practically verified that the MIC algorithm has the better performance. In fact, the results reveal that the MIC system could successfully perform the object manipulation task, as opposed to the AOM controller: for the same controller gains, the MIC strategy showed better performance than the AOM strategy. This means that because there is no control on the robot base with the AOM algorithm, the object manipulation task cannot be satisfactorily performed whenever the desired path is not within the robot work space. On the other hand, with the MIC algorithm, satisfactory object manipulation is achieved for a mobile robotic system in which the robot base, the manipulator endpoints and the manipulated object shall be moved.

Practical implications

A simple conceptual model for cooperative object manipulation is considered, and a suitable setup is designed for practical implementation of the two ICs.

Originality/value

The basis of these two aspects or these two algorithms is fully studied and compared which is the foundation of this paper. For this purpose, a case study is considered, in which a space free-flying robotic system, which contains two 2-degrees of freedom planar cooperative manipulators, is simulated to manipulate an object using the above control strategies. The system also includes a rotating antenna and camera as its third and fourth arm. Finally, a simple conceptual model for cooperative object manipulation is considered, and a suitable setup is designed for practical implementation of the two ICs.

Details

Industrial Robot: An International Journal, vol. 44 no. 2
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 17 February 2012

Jianhua Su, Hong Qiao, Zhicai Ou and Yuren Zhang

The purpose of this paper is to give a novel sensor‐less manipulation strategy for the high‐precision assembly of an eccentric peg into a hole.

Abstract

Purpose

The purpose of this paper is to give a novel sensor‐less manipulation strategy for the high‐precision assembly of an eccentric peg into a hole.

Design/methodology/approach

Based on the authors' previous work on the attractive region, this paper proposes the sensorless eccentric peg‐hole insertion strategy. The analysis is based on the visible strategic behaviors by decomposing the high‐dimensional configuration space of the eccentric peg‐hole into two low dimensional configuration subspaces. Then, the robotic manipulations can be designed in the configuration subspaces. Finally, a typical industry application, fitting an eccentric crankshaft into a bearing hole of the automotive air‐conditioners, is used to validate the presented strategy.

Findings

The attractive region constructed in the configuration space has been applied to guide the robotic manipulations, such as, the locating and the insertion.

Practical implications

The designed robotic assembly system without using force sensor or flexible wrist has an advantage in terms of expense and durability for the automotive air‐conditioners manufacturing industry.

Originality/value

Most previous work on sensorless manipulation strategy has concentrated on inserting a symmetric peg into a hole. However, for the assembly of an eccentric peg into a hole, the robotic manipulations should be explored in a high‐dimensional configuration space as the six‐DOFs of the eccentric peg. In this paper, the decomposition method of the high‐dimensional configuration space would make the system analysis visible; then, the assembly strategy can be easily designed in the two subspaces.

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Article
Publication date: 28 August 2007

C. Zieliński, W. Szynkiewicz, T. Winiarski, M. Staniak, W. Czajewski and T. Kornuta

This paper seeks to develop universal software (a programming framework) enabling the implementation of service robot controllers. The software should distinguish the…

Abstract

Purpose

This paper seeks to develop universal software (a programming framework) enabling the implementation of service robot controllers. The software should distinguish the hardware‐oriented part of the system from the task‐oriented one. Moreover, force, vision as well as other sensors should be taken into account. Multi‐effector systems have to be considered.

Design/methodology/approach

The robot programming framework MRROC++ has been implemented as a hierarchical structure composed of processes, potentially consisting of threads. All of the software is written in an object‐oriented manner using C++ and is supervised by a QNX real‐time operating system. The framework has been verified on several systems executing diverse tasks. Here, a Rubik's cube puzzle‐solving system, consisting of two arms and utilizing force control and visual servos, is presented.

Findings

The presented framework is well suited to tasks requiring two‐handed manipulation with force sensing, visual servoing and online construction of plans of actions. The Rubik's cube puzzle is a reasonable initial benchmark for validation of fundamental service robot capabilities. It requires force sensing and sight coupled with two‐handed manipulation and logical reasoning, as do the majority of service tasks. Owing to the use of force sensing during manipulation, jamming of the faces has always been avoided; however, visual servoing could only cope with slow handing over of the cube due to the volume of computations associated with vision processing.

Research limitations/implications

The proposed software structure does not limit the implementation of service robot controllers. However, some of the specific algorithms used for the solution of the benchmark task (i.e. Rubik's cube puzzle) need to be less time‐consuming.

Practical implications

The MRROC++ robot programming framework can be applied to the implementation of diverse robot controllers executing complex service tasks.

Originality/value

A demanding benchmark task for service robots has been formulated. This task, as well as many others, has been used to validate the MRROC++ robot programming framework which significantly facilitates the implementation of diverse robot systems.

Details

Industrial Robot: An International Journal, vol. 34 no. 5
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 20 October 2014

Ping Zhang, Guanglong Du and Di Li

The aim of this paper is to present a novel methodology which incorporates Camshift, Kalman filter (KFs) and adaptive multi-space transformation (AMT) for a human-robot…

Abstract

Purpose

The aim of this paper is to present a novel methodology which incorporates Camshift, Kalman filter (KFs) and adaptive multi-space transformation (AMT) for a human-robot interface, which perfects human intelligence and teleoperation.

Design/methodology/approach

In the proposed method, an inertial measurement unit is used to measure the orientation of the human hand, and a Camshift algorithm is used to track the human hand using a three-dimensional camera. Although the location and the orientation of the human can be obtained from the two sensors, the measurement error increases over time due to the noise of the devices and the tracking errors. KFs are used to estimate the location and the orientation of the human hand. Moreover, to be subject to the perceptive limitations and the motor limitations, human operator is hard to carry out the high precision operation. An AMT method is proposed to assist the operator to improve accuracy and reliability in determining the pose of the robot.

Findings

The experimental results show that this method would not hinder most natural human-limb motion and allows the operator to concentrate on his/her own task. Compared with the non-contacting marker-less method (Kofman et al., 2007), this method proves more accurate and stable.

Originality/value

The human-robot interface system was experimentally verified in a laboratory environment, and the results indicate that such a system can complete high-precision manipulation efficiently.

Details

Industrial Robot: An International Journal, vol. 41 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 2 August 2011

Ruhizan Liza Ahmad Shauri and Kenzo Nonami

The purpose of this paper is to propose an assembly robot that exhibits specific human‐like skills, with minimal structural cost and a number of external sensors.

Abstract

Purpose

The purpose of this paper is to propose an assembly robot that exhibits specific human‐like skills, with minimal structural cost and a number of external sensors.

Design/methodology/approach

The authors have employed vision processing using multiple cameras to determine targets and postures and propose strategies to determine the pose of a target and to prevent collisions between the fingers and obstacles in an environment with mixed objects. Furthermore, a dynamic trajectory planner integrates the vision and force sensors of the robot hand for the assigned task.

Findings

The authors obtained satisfactory experimental results for autonomous real‐time grasping and screwing. The results verified the capability of the robot for handling small objects.

Research limitations/implications

More effective robotic manipulation requires a higher degree of target orientation data, which will be a future study of this research.

Practical implications

Practicality has been established through results, indicating the capability of the robot to implement human‐like skilled manipulation of small objects. This can potentially reduce the high labor cost associated with the small‐scale manufacture of custom‐made products.

Originality/value

Screwing of nuts of minimum M2 size (diameter, 4.6 mm) and M8‐M10 bolts (head diameter, 15‐19.6 mm; length, 50‐80 mm) by cooperating two seven‐link arm manipulators and three‐fingered hands shows the robot's capability to manipulate small objects.

Details

Assembly Automation, vol. 31 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 21 August 2009

Ming Xie, Lei Wang, Xian Linbo, Jing Li, Hejin Yang, Chengsen Song and Li Zhang

Autonomous mobile manipulation depends on a lot of effort at various levels. In general, the hardware design is as important as algorithm (or software) design. In…

Abstract

Purpose

Autonomous mobile manipulation depends on a lot of effort at various levels. In general, the hardware design is as important as algorithm (or software) design. In particular, the absence of certain capabilities of hardware can seriously affect the feasibility and performance of algorithms. The purpose of this paper is to present work on developing hardware capability for mobile manipulation by low‐cost humanoids (LOCH) humanoid robot.

Design/methodology/approach

This paper presents research work on developing the hardware support which enables vision‐guided mobile manipulation realized on top of a biped humanoid robot called LOCH. One important goal which guides the development is to achieve the hardware capability with human‐like dexterity, modularity, functionality, and appearance.

Findings

This paper discusses the detail of solutions leading to the realization of the intended hardware capability, focusing in particular on the issues related to mechanism, actuation, distributed sensing, and distributed control of humanoid head, humanoid hands and humanoid arms. Finally, the paper shows the result of the actual prototype, which can be controlled by a remote control station through wireless connection.

Research limitations/implications

In designing a machine, it is common to do motor‐sizing and material selection. Since these are standard procedures, these details are omitted because readers with the training in mechanical engineering should be able to work out such details in order to select the appropriate motors and materials. Also, this paper does not delve into the description of the biped system of LOCH humanoid, because such work requires another long paper in order to reveal major details.

Originality/value

This paper presents the major detail of research efforts toward developing hardware capabilities for achieving autonomous mobile manipulation by LOCH humanoid robot, focusing on three important modules, namely: perception head, human‐like hands, and arms. The uniqueness of this work is twofold. First, LOCH humanoid robot's perception head has the most versatile sensing capabilities, which are fully integrated into a compact and human‐like head. Second, each of LOCH humanoid robot's hands has 14 degrees of freedom, which are realized within a mechanism which is of human‐hand size and shape. In addition, the perception head, humanoid hands and humanoid arms are seamlessly integrated together owing to the adoption of a distributed system which supports networked sensing and control through the use of both control area network bus and transmission control protocol/internet protocol internet.

Details

Industrial Robot: An International Journal, vol. 36 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

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